Happiness is difficult to define and even harder to measure. We experience it as a combination of elements, in the same way that one wheel or spring inside a watch doesn't keep time  it is a result of the synchronicity of the whole. As a relative state, happiness is what psychologists call our "subjective well-being" and, fortunately for us, it is a state that we can actively change for the better. Here are 20 ways to start.

Seek Positive Emotion as a Path to Success

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Happiness can lead to success, rather than just the other way around. Happy individuals are predisposed to seek out new opportunities and set new goals. After reviewing data of 225 studies gathered from more than 275,000 individuals, a team of psychologists concluded that while previous research assumed that happiness stemmed from success and accomplishment, happiness is often a result of positive emotions. Success is the result of many factors, including physical health, intelligence, family and expertise.